Minimal design thoughts

[bjornhallberg]

@tbowmo I found an old post I made here:
http://forum.mysensors.org/topic/413/is-there-a-schematic-of-the-nrf24-board/2
I checked the measurements and they seem right. In addition, the antenna-area is about 8mm long.

[tbowmo]

@bjornhallberg

made a mockup of the nrf24 mini module, and tried to place it on the sensor board.. If I should use it, I have to remove the ISP pinheader from the board, as there is no room for it.

Also, it is filling up almost half the populated pcb area on the sensor board, which means that there is not enough space for the components, and we have to make a bigger pcb, in order to have room for everything.

[bjornhallberg]

@tbowmo Yeah, better to save it for a future project. I mean, there will never be a one size fits all and that is what is so great about MySensors. All the PCBs designed so far have a purpose and a market. And ideally, we'd want a few of each in the sensor network to complement each other.

The reason I brought up the "mini", aside from wanting a flatter sensor node, is that the module seems to be getting more common on Ebay as well as cheaper. I've seen some sellers that sell them for the same price as the regular NRF24 now (in 10pcs). Four months ago, they were rare and many times more expensive. So if they work as advertised they could soon replace the NRF24 module we've all come to use.

In this context, and knowing very little of antennas, it is too bad they don't have a version without the PCB antenna altogether. We could add our own antennas and more easily fit the module on miniscule sensor nodes such as yours.

[tlund]

I would be interested in 5 units. I lean towards including ATSHA204 and smt assembled, but I would buy without and unassembled.

[tbowmo]

@tlund

So you would just buy the PCB, and source all components yourself?

[tlund]

@tbowmo
Sorry I was a bit unclear. I would like to buy all components as a package from you/mysensors. Preferably assembled, but I would also accept if you sell it unassembled (pcb+components). I would rather not have to source the components myself :)

Btw, have you measured the actual power consumption? Sleep vs temp/hum measurement?

[tbowmo]

@tlund

I haven't measured supply current, as I don't have the equipment to do that. I am looking at getting the uCurrent gold from eevblog, but it's expensive to import it to Denmark.

It will probably not be offered as a kit. Too much work from my/our part :-)

[hek]

@tbowmo said:

uCurrent gold

I can probably test it using mine. Any plans going to Skåne soon ;)

[Alphalove]

Hello, I'd be in for at least 5 assembled boards.

[A Former User]

Soo .. this like a breadmix ? :) All we have to add is the sensors ?

[tbowmo]

@hek

You already got an ucurrent? I had planned to import an extra one from Australia for you :) (thought that we might be able to save some $ if we ordered 4-5 units).

But as so many other things i got away from it again :(

Unfortunately I only come to Copenhagen these days, visiting a client.

[tbowmo]

@JimmyH

There is a temperature / humidity sensor on it already. But more can be added :)

[hek]

Ok, pushed a product page to the main site just now. Hope the page is selling enough. ;)

http://www.mysensors.org/hardware/micro

[RJ_Make]

"ATSHA204A sot23 footprint on board"

So does that mean this run will not have the ATSHA204A populated?

[tbowmo]

@ServiceXp

We haven't started production yet, I'm still waiting for the latest prototype pcb to arrive from China, before I can make the (hopefully) last prototype before "mass production". Which also means I have to find the atsha204 somewhere, so I can test it.

And yes I know mouser has it, but I don't need that much more from them, so will have to pay a big handling/shipping fee to them

[hek]

@Anticimex , did you have any spare atsha204 left?

[bjornhallberg]

@tbowmo Have you looked on AliExpress. A quick search seems to suggest that could be a viable alternative. Try some different search combinations though ... their search engine sucks. "ATSHA204" wont find "ATSHA204A" for instance when I try.

Wont be quick though, and the Chinese New Year is coming up ...

[Anticimex]

I can part with a SOT23 ATSHA204A if necessary. They can also be sampled from Atmel in small quantities for free (that's what I did).

[hek]

@Anticimex said:

sampled

Do you remember the deliver time on samples?

[Anticimex]

@hek It took three days from order confirmation to shipment notification. I don't recall the transit times but it went out with DHL WW Express so it should be pretty fast. Say 5-10 working days tops.